In Pontifex you design and build bridges. Once your bridge design is completed the bridge is tested by trains traveling across it. As you watch, the vehicles will either pass over safely or plummets into the river below depending on your design. Pontifex uses complex physics which allows for many different types of bridges to be built and tested. The 3D graphics engine allows you to view your bridge from any angle including a first-person train view. Pontifex II includes many types of levels varying in difficulty from simple to complex. It also includes a level editor with which you can create your own levels to trade with other people.